Method of recovering soluble beryllium compounds



Sept. 30, 1930. H. LOEWENSTEIN METHOD OF RECOVERING SOLUBLE BEHYLLIUM COMPOUNDS Filed Sept. 18, 1929 Patented Sept. 30, 1930 UNITED STATES PATENT OFFICE HIRSCE LOEWENSTEIN, OF KABLBBUHE IN BADEN, GERMANY METHOD OF RECOVEBIN SOLUBLE BIKRYLLIUM COMPOUNDS Application filed September 18, I29, Serial No. 393,450, and in Germany September 25, 1928.

The inventionrelates to a novel method furnace and associated condensing and sepaof recovering beryllium in the form of solurating apparatus. I ble compounds, such as oxide or sulfide of Fig. 2 is a similar view of another type metal from beryllium containing materials of electric furnace with ancillary fractional 5 or natural minerals such as beryl, phenacite condensers interposed between the furnace and the like, said method involving the heat and the condensing and separating appatreatment of the raw material in admixture ratus. with a reducing agent, preferably sulfur or In carrying out the method the material a sulfur containing compound, under concontaining beryllium is preferably mixed 10 ditions that will result in the production of with sulfur .or sulfur compounds, such for the readily available compounds of the example, as pyrites or ferrous sulfide and a metal, which are concurrently volatilized and reducing agent, such as carbon. A reducing subsequently condensed. gas must be used. Sulfur in a free state or Beryllium occurs in beryl, phenacite and in the form of hydrogen sulfide, may serve 15 similar minerals accompanied by silicates of as a reducing agent, as may also other realuminum, iron and other metals. It is a lated reduction agents, such as calcium cardesideratum in the art to recover beryllium bide or silicon. Preferably, when sulfur is in available form from these silicates, the employed it should be insufficient quantit recovered material being as pure as may be. to insure that all of the aluminum and bery 20 In the present invention this object is atlium present in the raw material ma comtained by subjecting the silicate to a high bine therewith. The mixture is then eated, temperature under reducing conditions and preferably in the presence of neutral gases in usually in the presence of sulfur; the teman electric furnace, which may be of any of perature being high enough to form and the usual types, such as an arc furnace or an vaporize volatile beryllium compounds (oxinduction furnace, to a temperature sufiicient ide and sulfide). The reduction is usually to effect the reduction of the beryllium to the sufficient to reduce the iron oxide and silica form of oxide or sulfide, which temperature is present, thereby forming a ferrosilicon but also sufficient to volatilize the beryllium comis not suflicient to produce metallic aluminpound and possibly part of the aluminum um or metallic beryllium. In the event of compound, the volatilization being enhanced the presence of sulfur, however, reduction by carrying out the operation under reduced can go somewhat further in order to form pressure or partial vacuum within the fursulfides of beryllium and aluminum. An nace. Inasmuch as the resulting beryllium admixture of iron pyrite with the charge compound is volatilized at a lower temperaassists reduction and gives sulfur and iron ture than the aluminum compounds, it is postoform ferrosilicon with reduced silica. An sible, by carefully regulating the temperelectric furnace is ordinarily used. The ature, to secure a substantially complete vapors may contain beryllium oxide or sulvolatilization of the desired beryllium comfide or both and aluminum oxide or sulfide pounds with a relatively small portion of 40 or both. Generally, the vapors evolved are volatilized aluminum compounds which subsubmitted to fractional condensation to sepasequently may be readily separated. The rate alumina and beryllia to a certain extent. volatile constituents of the reaction are then The beryllium compounds are more volatile led from the furnace to the condensing and than the aluminum compounds and condense separating apparatus or, if found-necessary, 5 later. the fumes may be first led through a separat- Suitable forms of apparatus for carrying ing device which will extract all of the solid out the method are more or less diagrammaterial therefrom and thence through spematically illustrated in the accompanying cial forms of "fractional condensers which drawings, in which: operate to maintain the beryllium com- Fig. 1 is a sectional elevation of an electric pounds in gaseous condition, while permitting the concurrentlv fmmnA aluminum compounds to condense and separate therefrom, the gaseous beryllium compounds then being passed through suitable condensers and separators, whence said compounds may be recovered for subsequent use.

Similarly a fractional condenser may be employed into which the admixed fumes from the furnace are delivered, the temperatures of the various sections of the condenser being so regulated as to first condense the undesired vapors and, finally, to corn dense and'throw down the desired beryllium compound or compounds in the form of oxide or sulfide, or both.

If found more expedient the separation of the sublimates may be effected afterthe condensing operation, by any suitable means or treatment.

In Fig. 1-of the drawings a relatively simple form of apparatus for carrying out the method is illustrated, said apparatus comprising an electric furnace comprising a casmg 1, preferably provided with a refractory lining, in the top of which is slidably mounted the support for the movable electrode 2, which cooperates with a fixed electrode 4, preferably in the form of a carbon plate mounted near the bottom of the furnace, and which maybe cooled by suitable water circulating means, the upper or movable electrode being controlled and maintained in arcing relation with the plate 4 by suitable controlling means diagrammatically indicated at 3. The electrodes and their supports are suitably insulated, and are mounted in the furnace in air-tight relation so that the interior of the furnace may be maintained at sub-atmospheric pressure or partial vacuum, which will be indicated by a manometer 5.

The mixture of the raw beryllium materials and the reducing agent is charged into the furnace between the electrodes, and the are between the latter serves to raise the temperature of the ingredients of the mixture to effect the formation from the raw beryllium containing materials of beryllium oxide or sulfide, or both, according to the character of the reagents admixed with the raw beryllium materials, and also to vaporize the stated beryllium compounds together with some of the resultant aluminum compounds. Iron oxide and silica are reduced and form ferrosilicon. The vapors pass off through the discharge opening at the top of the furnace into a condenser and separator 6, which may be of the well known zigzag type, in which major portions of the volatilized mineral values are successively condensed and are collected in the hopper like bottom sections of the apparatus 6, from which they may be discharged by suitable gated outlets 7 in the hopper bottoms. The temperature in the condenser may be so regulated that the aluminum compounds will be separated in the first portion of the condenser, while most of the volatile beryllium compounds will be condensed in the following sections of the condenser. From the condenser 6, the residual gaseous constituents are passed through a bag filter 8, of usual construction, which will separate the permanent gases from any entrained beryllium compound entrained therewith.

In the apparatus illustrated in Fig.2, the electric furnace comprises a suitable chamber 10, with are electrodes 11 passing through the sides thereof and provided with the usual regulating apparatus, not shown, the electrodes being sodisposed that the arcv plays directly into'the body of the mixture which is fed intermittently as desired into the furnace from a suitable valved hopper 12. Connected to the outlet of the furnace is one or more vertical columns 14, preferably formed of refractory material and'provided with a lining 15 of carbon, which is adapted to be heated by a suitable electric resistance apparatus 16 associated therewith, the temperature generated in the linings being so regulated as to maintain the beryllium reaction products in gaseous condition while passing therethrough, but insuflicient to maintain the fumes of the aluminum or other foreign reaction products produced, so that the latter are condensed and fall to the bottom of the columns, I whence they may be discharged from time to time by means of suitable gates 17. These columns constitute fractional condensers which are effective in separating the fumes of the beryllium compounds from all foreign materials which are less volatile than said compounds, so that when the beryllium compound fumes eventually pass through the condenser 18 and the bag filter 20, said compounds will be condensed in the form' of substantially pure sublimate, which latter may be discharged from the hopper bottoms of the several sections of the condenser by the gate valves 19.

As a particular example of the operation of the method carried out in the apparatus illustrated in Fig. 1, 1 kg. of beryl was mixed with 2% kg. of pyrites and 100 gr. of carbon. This particular amount of carbon was employed for the purpose of reducing the entire content of iron and silicon present, but was not sufiicient to effect reduction of the aluminum or beryllium. The furnace was heated for 4 hours with a current of 200 amp. 40 to 60 volts and under an internal pressure within the furnace of 720 mm., which was maintained by the pump attached to the end of the bag filter. When the operation was completed and the furnace had been permitted to cool, there was found at the bottom an alloy of ferrosilicon covered with slag, in which only traces of beryllium could be found. The sublimation products were largely recovered in the condenser or dust chamber 6, and consisted of the soluble beryl lium compounds desired, together with a small portion of carbon, iron and aluminum as impurities, most of which latter being deposited in the first sections of the condenser or dust chamber, so that it was found that the forward sections of the condenser contained practically all of the impurities with not more than40% of the soluble beryllium compounds, while in the following and final chambers of the condenser or dust chamber, substantially pure beryllium compounds of the character desired were recovered.

What I claim is:

l. The. method of treating beryllium containing silicate minerals, which comprises mixing the raw materials with a reducing agent, heating the mixture to efiect reduction of the silica to silicon and a transformation of the beryllium constituents into available compounds with simultaneous volatilization of such compounds, and production of a residue containing silicon, and condensing the volatilization products.

2. The method of recoverin soluble compounds of beryllium from bery lium containing minerals, which comprises sublimating an admixture of the mineral and sul hur.

3. The method of recovering solub e compounds of beryllium from beryllium containing minerals, which com rises heating the mineral in the presence 0 sulphur to a temperature suflicicnt to volatilize the resultant reaction compounds of her llium, and condensing the volatilized products.

4. The method of recovering soluble compounds of beryllium from beryllium containing minerals, which compr ses heating the mineral in the presence of a metal sulfide to a temperature sufficient to volatilize the resultant reaction compounds of beryllium, and condensingthe volatilized products.

5. The method of recovering soluble compounds of beryllium from beryllium containing minerals, which comprises heating the mineral in the presence of yrites to a temperature suflicient to volati ize .the nesultant reaction compounds of beryllium, and condensing the volatilized products.

6. The method of recovering soluble com pounds of her Ilium from beryllium containing minera s, which comprises heating the mineral in the presence of pyrites and carbon to a temperature suflicient to volatilize the resultant reaction compounds of beryllium, and condensing the volatilized products.

7. In the production of available beryllium compounds from beryl and like minerals the process which comprises heating sue a mineral under reducing conditions to a temperature sufiicient to effect reduction of silica to silicon and volatilization of beryllium oxide.

8. In the manufacture of available beryllium compounds from beryl and like minerals, the process which comprises heating a mixture of such a mineral and pyrite in the presence of carbon to a temperature suflicint to form ferrosilicon and vapors containing beryllium oxide or sulfide or 0th.

9. The method of recoverin soluble comounds of beryllium from bery lium-containmg silicate minerals, which comprises heat ing an admixture of the mineral and a reducing agent to sublime a beryllium compound and to form a residue containing silicon, thus separating the beryllium from the silicon.

In testimony whereof I aflix my signature.

HIRSGH LOEWENSTEIN. 

